Weird Material Problem

Hey, im currently building a Raytraced Scene with Unreals Automotive Material Pack.
All Materials have these weird tilings. What could be the Problem? I think its only a wrong setting checked, but i cant figure out which one…

Usually either a bad roughness map or a bad normal map.

The sphere is definitely not seamed that way.

The default engine one has a nice sphere unwrap actually, so if the issue were the UV seam it would appear as a straight vertical line.

If you used your own unwrapped sphere, then maybe the UVs are incorrect.
It does acrually look similar to how converting a cube to a sphere in blender via subdivision modifier would render out… but I don’t think that’s the issue.

Look at the different textures in use on the material instance.